Merge branch 'sololegends-phpcxs-flags-addition' into 'master'

Update PHPCS env flags in analyzer settings

See merge request gitlab-org/gitlab!31034

doc/user/application_security/sast/index.md

@@ -326,6 +326,7 @@ Some analyzers can be customized with environment variables.
 | `SBT_PATH`                            | SpotBugs             | Path to the `sbt` executable. |
 | `FAIL_NEVER`                          | SpotBugs             | Set to `1` to ignore compilation failure. |
 | `SAST_GOSEC_CONFIG`                   | Gosec                | Path to configuration for Gosec (optional). |
+| `PHPCS_SECURITY_AUDIT_PHP_EXTENSIONS` | phpcs-security-audit | Comma separated list of additional PHP Extensions. |
 
 #### Custom environment variables